Thoughts On Last Week’s Major Power Outage
This article on the BBC is entitled Major Power Failure Affects Homes And Transport.
This is the first two paragraphs.
Nearly a million people have been affected by a major power cut across large areas of England and Wales, affecting homes and transport networks.
National Grid said it was caused by issues with two power generators but the problem was now resolved.
This second article on the BBC is entitled UK power cut: Why it caused so much disruption, and gives these details.
It started with a routine blip – the gas-fired power station at Little Barford in Bedfordshire shut down at 16:58 BST due to a technical issue.
Then, a second power station, the new Hornsea offshore wind farm, also “lost load” – meaning the turbines were still moving, but power was not reaching the grid.
These are my thoughts on the incident.
Power Stations Do Fail
Any complex electro-mechanical system like Little Barford gas-fired power station or Hornsea offshore wind farm can fail.
- Little Barford gas-fired power station was built in 1994 and is a 746 MW gas-fired power station.
- Hornsea offshore wind farm obtained planning permission in 2014 and is being built in phases. It will eventually have a maximum capacity of 8 GW or 8,000 MW.
Compare these figures with the iconic coal-fired Battersea power station, which had a maximum output of 503 MW in 1955.
I will not speculate as to what wet wrong except to say that as the Hornsea wind-farm is relatively new, it could be what engineers call an infant mortality problem. Complex systems or even components seem to fail in the first few months of operation.
Why Do We Have Gas-Fired Stations?
According to this page on Wikipedia, there are around forty natural gas fired power stations in England.
Most gas-fired stations are what are known as CCGT (Combined Cycle Gas Turbine), where a Jumbo-sized gas-turbine engine is paired with a steam turbine powered by the heat of the exhaust from the engine.
This form of power generation does produce some carbon dioxide, but to obtain a given amount of electricity, it produces a lot less than using coal or ioil.
By combining the gas turbine with a steam turbine, the power station becomes more efficient and less carbon dioxide is produced.
Power stations of this type have three various advantages.
- They have a very fast start-up time, so are ideal power stations to respond to sudden increases in electricity demand.
- As they are a gas-turbine engine with extra gubbins, they are very controllable, just like their cousins on aircraft.
- They are relatively quick, easy and affordable to build. The Wikipedia entry for a CCGT says this. “The capital costs of combined cycle power is relatively low, at around $1000/kW, making it one of the cheapest types of generation to install.”
- They don’t need a complicated and expensive transport infrastructure to bring in coal or nuclear fuel.
- They can also be powered by biogas from agricultural or forestry waste, although I don’t think that is a comm practice in the UK.
The carbon dioxide produced is the only major problem.
Gas-Fired Power Stations In The Future
If you read the Wikipedia entry for combined cycle power plants, there is a lot of information on CCGTs, much of which is on various ways of improving their efficiency.
I believe that one particular method of increasing efficiency could be very applicable in the UK.
Under Boosting Efficiency in the Wikipedia entry, the following is said.
The efficiency of CCGT and GT can be boosted by pre-cooling combustion air. This is practised in hot climates and also has the effect of increasing power output. This is achieved by evaporative cooling of water using a moist matrix placed in front of the turbine, or by using Ice storage air conditioning. The latter has the advantage of greater improvements due to the lower temperatures available. Furthermore, ice storage can be used as a means of load control or load shifting since ice can be made during periods of low power demand and, potentially in the future the anticipated high availability of other resources such as renewables during certain periods.
The UK is the world’s largest generator of power using offshore wind and as we are surrounded with sea and wind, the UK is only going to produce more of the power it needs in this or other way.
This method could be used to store the wind energy produced when the demand is low and recover it, when it is needed.
Could The UK Develop A Chain Of Carbon-Neutral Gas-Fired Power Stations?
In parts of the UK, there is a unique mix of resources.
- A plentiful supply of natural gas, either from offshore fields or interconnectors to Norway.
- Large amounts of electricity generated by offshore wind, which will only get larger.
- Worked out gas-fields still connected to the shore, through redundant platforms and pipes.
- Closeness to agricultural areas.
Technologies under development or already working include.
- Offshore creation of hydrogen using electricity generated by offshore wind and then using the redundant gas pipes to bring the hydrogen to the shore.
- Using a hydrogen-fired CCGT power station without producing any carbon-dioxide.
- Feeding carbon dioxide to plants like salad and fruit to make them grow better.
- Using excess electricity from renewable sources to cool the air and improve the efficiency of CCGT power stations.
I can see all these technologies and development coming together in the next few years and a chain of carbon-neutral gas-fired power stations will be created
- Hydrogen produced offshore on redundant gas platforms, using electricity from nearby wind farms, will be turned back into electricity, where it is needed by onshore hydrogen-fired power stations.
- Redundant gas platforms will be refurbished and reused, rather than demolished at great expense.
- Some natural gas will still be used for power generation
- I’m not quite sure, but I think there could be dual-furled CCGTs, that could run on either hydrogen or natural gas.
- Any carbon dioxide generated will be stored in the worked out gas fields or fed to the crops.
- Gas storage onshore will ensure that the gas-fired power station can respond quickly.
I also believe that there is no technological and engineering challenges, that are too difficult to solve.
This strategy would have the following advantages.
- It should be carbon-neutral.
- Because there could have as many as two hundred individual power stations, the system would be very reliable and responsive to the loss of say a cluster of five stations, due to a tsunami, a volcanic eruption or a major eathquake.
- If power from renewable sources like offshore wind is low, extra stations can be quickly switched in.
- It is not dependent on fuel from dodgy dictators!
- It would probably be more affordable than developing nuclear power stations.
There is also the possibility of bringing more hydrogen onshore to be used in the decarbonisation of the gas-grid.
Conclusion
A chain of carbon-neutral gas-fired power stations, linked to hydrogen created offshore by wind farms is very feasible.
Last week, after the double failure, extra stations would have immediately been switched in.
Energy Storage
The fastest response system is energy storage, where a giant battery holds several gigawatt-hours of eklectricity.
Electric Mountain
The biggest energy storage facility in the UK is Dinorwig Power Station.
This is the introduction to its Wikipedia entry.
The Dinorwig Power Station , known locally as Electric Mountain, is a pumped-storage hydroelectric scheme, near Dinorwig, Llanberisin Snowdonia national park in Gwynedd, northern Wales. The scheme can supply a maximum power of 1,728-megawatt (2,317,000 hp) and has a storage capacity of around 9.1-gigawatt-hour (33 TJ)
It is large and has a rapid response, when more electricity is needed.
We probably need another three or four Electric Mountains, but our geography means we have few suitable sites for pumped-storage, especially in areas, where large quantities of electricity are needed.
There are one other pumped-storage system in Wales and two in Scotland, all of which are around 350 MW or a fifth the size of Electric Mountain.
In the Wikipedia entry entitled List Of Power Stations In Scotland, this is said.
SSE have proposed building two new pumped storage schemes in the Great Glen; 600 MW at Balmacaan above Loch Ness, and 600 MW at Coire Glas above Loch Lochy, at £800m. Scotland has a potential for around 500 GWh of pumped storage
I’m sure the Scots will find some way to fill this storage.
If all else fails, there’s always Icelink. This is the description from Wikipedia.
Icelink is a proposed electricity interconnector between Iceland and Great Britain. As of 2017, the project is still at the feasibility stage. According to current plans, IceLink may become operational in 2027.
At 1000–1200 km, the 1000 MW HVDC link would be the longest sub-sea power interconnector in the world.
The project partners are National Grid plc in the UK, and Landsvirkjun, the state-owned generator in Iceland, and Landsnet, the Icelandic Transmission System Operator (TSO)
Plugging it in to Scotland, rather than London, probably saves a bit of money!
Conclusion
Increasing our pumped-storage energy capacity is feasible and would help us to survive major power failures.
Batteries In Buildings
Tesla have a product called a Powerwall, which puts energy storage into a home or other building.
This was the first product of its kind and there will be many imitators.
The Powerwall 2 has a capacity of 13.5 kWh, which is puny compared to the 9.1 GWh or 9,100,000 kWh of Electric Mountain.
But only 674,074 batteries would need to be fitted in the UK to be able to store the same amount of electricity as Electric Mountain.
The big benefit of batteries in buildings is that they shift usage from the Peak times to overnight
So they will reduce domestic demand in the Peak.
Conclusion
Government should give incentives for people to add batteries to their houses and other buildings.
Could Hydrogen Work As Energy Storage?
Suppose you had a hydrogen-fired 500 MW hydrogen-fired CCGT with a hydrogen tank that was large enough to run it at full power for an hour.
That would be a 0.5 GWh storage battery with a discharge rate of 500 MW.
In an hour it would supply 500MWh or 500,000 kWh of electricity at full power.
In Hydrogen Economy on Wikipedia, this is said, about producing hydrogen by electroysis of water.
However, current best processes for water electrolysis have an effective electrical efficiency of 70-80%, so that producing 1 kg of hydrogen (which has a specific energy of 143 MJ/kg or about 40 kWh/kg) requires 50–55 kWh of electricity.
If I take the 40 KWh/Kg figure that means that to provide maximum power for an hour needs 12,500 Kg or 12.5 tonnes of hydrogen.
Under a pressure of 700 bar, hydrogen has a density of 42 Kg/cu. m., so 12.5 tonnes of hydrogen will occupy just under 300 cubic metres.
If I’ve got the figures right that could be a manageable amount of hydrogen.
Remember, I used to work in a hydrogen factory and I had the detailed guided tour. Technology may change in fifty years, but the properties of hydrogen haven’t!
Gas-Fired Versus Coal-Fired Power Stations
Consider.
- The problem of the carbon dioxide is easier with a gas-fired power station, than a coal-fired power station of the same generating capacity, as it will generate only about forty percent of carbon dioxide.
- Gas-fired power stations can be started up very quickly, whereas starting a coal-fired power station probably takes all day.
- Coal is much more difficult to handle than gas.
Using hydrogen is even better than using natural gas, as it’s zero-carbpn.
Conclusion
I believe we can use our unique geographic position and proven technology to increase the resilience of our power networks.
We need both more power stations and energy storage.
This Is What I Call A MOAB
Jamestown is a small Australian town of a few over fourteen hundred souls, probably home to several million flies and some of the most venomous spiders and snakes known to man.
I have never visited the town, but I must have flown nearly over it, when I flew a Piper Arrow around Australia with C.
Just to the North of the town is the Hornsdale Wind Farm, which consists of 99 wind turbines with a generating capacity of 315 MW.
But this is not what brought the wind farm to my attention in an article in today’s Times under a headline of Biggest Ever Battery Plugs City’s Energy Gap.
This is said.
The battery array was built after a high-stakes bet by Elon Musk, 46, the US technology billionaire behind Tesla electric cars, that he could meet a 100-day building deadline or he would give the system away.
Wikipedia has a section on this battery.
This is said.
South Australia received 90 proposals and considered 5 projects. Tesla, Inc. is building the world’s most powerful lithium ion battery adjacent to the wind farm. It has two sections; a 70 MW running for 10 minutes, and a 30 MW with a 3 hour capacity. Samsung 21700-size cells are used.
It will be operated by Tesla and provide a total of 129 megawatt-hours (460 GJ) of storage capable of discharge at 100 megawatts (130,000 hp) into the power grid. This will help prevent load-shedding blackouts and provide stability to the grid (grid services) while other generators can be started in the event of sudden drops in wind or other network issues. It is intended to be built in 100 days counting from 29 September 2017, when a grid connection agreement was signed with Electranet, and some units were operational. The battery construction was completed and testing began on 25 November 2017. It is owned by Neoen and Tesla, with the government having the ability to call on the stored power under certain circumstances.
It certainly seems to be the Mother-Of-All-Batteries! Hence MOAB!
The Times is reporting that the battery system has cost £30 million.
This works out at about £233,000 to store each Megawatt-Hour stored.
When you consider that we have five offshore that are bigger than the Hornsdale Wind Farm, surely it is only a matter of time before we add a battery to one.
These MOABs are an intriguing concept!
The Aussies Get Into Home Batteries
As you might imagine, Australia with its sunshine and lots of remote communities could be a big market for battery technology like Tesla’s Powerwall. But this article in the Australian Financial Review shows why the country will be a big market.
It says that for example in Queensland, a third of the houses have solar panels, which must only increase the demand for batteries.
But it also says that the way the Australians charge for electricity is different to the United States and this makes batteries much more useful. I think that in the UK, we follow the Australian model. Except for the sun of course!
The article has some interesting details on how the price of the devices will go, especially as it says that Panasonic who are one of the Big 3 battery makers will be entering the market soon.
I all think it goes to show that each market is different and I suspect that the UK market will be different again, as most of us don’t live in houses that are too friendly to solar panels.
But my house is with its flat roof, and I am watching the price of solar panels, because I reckon in the next few years, I’ll be able to fit a very affordable system, that will take me substantially off-grid, with a battery in the garage.
Solar panels, battery technology and small innovative energy companies are going to give the Big 6 energy companies, one hell of a kicking.
A Must Read Article On The Tesla Powerwall
I have a Google Alert set for Tesla Powerwall and usually it just picks up pretty boring stuff, but this article from ecomento.com is better than most. It does state this.
The Tesla Powerwall won’t really make economic sense for most US customers until the price drops – considerably. The people who buy one now will help fund the research and development that needs to take place to drive battery prices down in the future.
So as with a lot of new technology, with my engineer’s hard hat on, I think it will be best to wait until the cost of solar panels, Powerwall-like devices and all the other electronics and control systems needed, have been proven to be reliable and have dropped in price.
My house here has a flat roof, which would be ideal for solar panels, so I’m watching the technology and will buy them, when the payback is less than five years.
Why five years? It’s the length of our fixed term parliament, so hopefully the financial conditions won’t be mucked up too much by a change of governmen.
The Other Big News Of The Past Few Days
With the election hogging the news, some things haven’t been given full coverage by the media.
One is Elon Musks idea of the Powerwall, which is a battery storage device for electricity, described in this article in the Guardian and another piece on uSwitch.
This may all look like an expensive toy or gimmick perhaps with a few specialist applications, but I believe it is a technology that could become commonplace in the future.
The flow is with this device and as my trip on a battery-assisted train at Manningtree showed, btteries are no longer something to power milk-floats.
Using a battery in a modern energy-efficient home or business, which perhaps has a roof covered in solar panels is an interesting way of cutting out paid-for electricity, for a hopefully one-off purchase and installation payment.
I wouldn’t buy one now, as although the Powerwall is deliverable now, improvements in battery and solar panel technology will mean that the systems available in a few years will store and generate more electricity in a more affordable manner. I also suspect, we’ll see replacement window glass units, that can either let light through or capture it for electricity.
We will also see much better control systems, although I suspect the the one Powerwall has is pretty sophisticated.
So I’m hanging back now, but I will be looking to put solar panels on my flat roof in anticipation of these better storage systems.
Musk is right, when he says that energy storage is going to revolutionise the world. But I do think that there will be a host of better or improved ways to do it.
But there is work to do, as this image of south-facing roofs in Ipswich shows, solar panels are notable by their absence.
No Solar Panels
In a few years time, this image will show lots of solar panels.
It is another case of giving the engineers the money to finish the deveopment and householders the right sort of finance for installation, so everybody can realise the dream of a house that doesn’t use any paid-for electricity.
The Anonymous Widower 